1. Field of the Invention
This invention relates to a method of making a microcircuit device, and more particularly to a method of making a semiconductor device including a process of patterning electrodes and wiring by plasma etching.
2. Description of the Prior Art
In semiconductor devices such as a transistor, an integrated circuit, a large-scale integrated circuit and so on, electrodes or wiring is mostly formed of aluminum (A1) but sometimes formed of platinum (Pt), gold (Au), titanium (Ti), molybdenum (Mo) or the like, too. For patterning such a metal film material, a liquid etching solution employing an etchant is usually employed. In these processes using tungsten (W), a heated aqueous solution of potassium hydroxide or sodium hydroxide, HNO.sub.3 --HF mixed solution, a heated aqueous solution of hydrogen peroxide or the like may be employed as an etchant. However, when using an etching mask formed of a photoresist material, there are instances where the photoresist material vanishes or peels off during etching, so that accurate patterning is difficult.